1. Field of the Invention
The present invention relates to distress or emergency signalling devices, for use on sea or land, which are lifted into the air b lighter-than-air balloons, sails, or particularly by means including a parafoil such as used by sport parachutists.
2. Description of the Prior Art
Increasingly popular among outdoor sports are boating, hiking, cross-country skiing and the like. One factor such sports have in common is the possibility of participants becoming lost or other distress situations which require signalling the outside world for help and perhaps employing survival techniques while awaiting rescue. For example, the U.S. Coast Guard provides various recommendations and requirements for recreational boats or other vessels operating in coastal waters or the high seas. A variety of signals may be used for day and/or night signalling. Pyrotechnic visual distress signals include pyrotechnic red flares, hand-held or aerial; orange smokes, hand-held or floating; and launchers for aerial red meteors or parachute flares. Non-pyrotechnic visual distress signals include orange distress flags and electric distress lights. The distress flag, for day use only, must be at least three feet square, containing a black square and ball (circle) on an orange background. The electric distress light for night use can be a signal light flashing SOS signals or (under Inland Navigation Rules) a high intensity white light flashing 50-70 times per minute (i.e., a "strobe light").
With any of the signals described, mariners (or hikers, etc.) in distress encounter limitations in how long the signals (such as rockets or flares) persist and how far they can be seen (determined primarily by the size and altitude of the distress signal). Applicant has previously explored possibilities for raising distress signals to higher altitudes using devices such as the Jalbert parafoil used by sport parachutists. A parafoil is defined as a flexible structure made of lightweight fabric or the like, having a shape similar to that of an airplane wing (or airfoil) which can be used as a kite or parachute. Such parafoils are now available commercially in sizes ranging from those suitable for sport parachuting down to those which are effectively toy kites. Applicant's U.S. Pat. No. 4,497,272 discloses and claims "Mastless Sails", i. e., various combinations of parafoils, balloons and sails (such as a spinnaker) which can be used to provide extra propulsion to small boats or the like. Also, U.S. Pat. No. 4,178,867 cited therein discloses the use of a hydrogen-filled signal balloon to hold a rescue signal device aloft. Applicant's patent suggests (in col. 4 ) that visual recognition of such parafoil/spinnaker combinations can be enhanced by coloring them international orange. Communications means such as omnidirectional antennas can be used on such sails.
Despite the availability of a variety of Coast Guard-approved distress signals, there is growing demand for signals which may be more effective, convenient and useful, preferably qualifying for Coast Guard certification.